ASTM_D_1779_-_98_2011.pdf

Designation:D177998(Reapproved 2011)Standard Specification forAdhesive for Acoustical Materials1This standard is issued under the fixed designation D1779;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1.Scope1.1 This specification covers an adhesive for bonding pre-fabricated acoustical materials to the inside walls and ceilingsof rooms in buildings.This adhesive is required to maintain atensile adhesion(bond strength)of not less than 3.45 104dynes/cm2(12lb/in.2)for a long period of time under thetemperature and moisture conditions likely to be encounteredand to maintain sufficient plasticity to allow for movement ofparts of the building as it ages.NOTE1Cleanliness of SurfaceThe surface to which the acousticalmaterial is applied with the adhesive should be clean,sound,and dry.Surface coatings should be removed if their nature indicates an unsatis-factory installation,so that the adhesive can be applied to the base.Whenthe adhesive is to be applied on a painted surface,test tile should beapplied for 48 h to determine suitable adherence of the coating byexamination.Acoustical adhesives are not intended to be applied tosurfaces that are moist and that have an alkaline reaction,or that may laterbecome moist or alkaline.Such surfaces,as concrete or plaster,should beproperly dried and aged before applying the adhesive.NOTE2LoadThis adhesive is not recommended as a sole means ofholding acoustical materials weighing more than 121 kg/m2(212lb/ft2)toceiling surfaces.NOTE3Amount and Condition of MaterialIt is recommended thatsufficient adhesive be used so that there is a contact surface of not less than1.2 104cm2/m2(20 in.2/ft2)of acoustical material,with a minimumthickness of 0.3 cm(18in.)and that the adhesive be applied in fourseparate nearly spherical portions of approximately equal size near thecorners for a standard 30.5 by 30.5-cm(12 by 12-in.)tile.Fewer than ormore than four portions for 30.5 by 30.5-cm tile are not recommended dueto difficulty in leveling and in securing effective contact area on allportions.Adhesives that are hard,or do not wet the surface,or are difficultto spread should not be used.NOTE4Rigidity of Base SurfacesIt is necessary that the materialforming the base to which the adhesive is attached should be relativelysmooth,firm,and rigid.If the pressure of applying tile and adhesivecauses the base material to deflect excessively,tile previously applied mayhave their adhesive bond broken.This occurs on some types of gypsumboard suspension systems.NOTE5AgingTo date,no accelerated aging tests for adhesives havebeen developed to duplicate exactly aging in service.The aging tests inthis specification are designed to accelerate the aging process and to testvarious manifestations of aging,and are intended to be satisfactory forcomparing one adhesive with another;they do not necessarily reflect agingcharacteristics on an absolute basis.Purchasers of adhesives shouldreceive from the manufacturer additional warranties and assurances ofperformance of the adhesive under normal aging.NOTE6Erection PracticesProper erection techniques are essentialfor proper performance of any acoustical adhesive.Use of a materialmeeting this specification will not in itself guarantee satisfactory perfor-mance.Only when tiles are applied by skilled and experienced workersfollowing instructions from the manufacturer can the purchaser be assuredof satisfactory performance of an adhesive.1.2 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2C37/C37M Specification for Gypsum Lath(Withdrawn2004)3D618 Practice for Conditioning Plastics for TestingD907 Terminology of AdhesivesE104 Practice for Maintaining Constant Relative Humidityby Means of Aqueous Solutions2.2 Federal Specification:MMM-A00150BInterim Federal Specification forAcoustical Materials43.Terminology3.1 DefinitionsMany terms in this specification are de-fined in Terminology D907.1This specification is under the jurisdiction of ASTM Committee D14 onAdhesives and is the direct responsibility of Subcommittee D14.70 on ConstructionAdhesives.Current edition approved Jan.1,2011.Published January 2011.Originallyapproved in 1960.Last previous edition approved in 2004 as D1779 98(2004).DOI:10.1520/D1779-98R11.2For referenced ASTM standards,visit the ASTM website,www.astm.